Registration Number under the Investment Company Act of 1940: 811-05201

Ladies and Gentlemen:

On behalf of the above-referenced Registrant and pursuant to Rule 497 under the Securities Act of 1933, as amended, I have attached for filing exhibits containing interactive data format risk/return
summary information. These interactive data files relate to the prospectus supplement that the Registrant filed with the Securities and Exchange Commission on October 2, 2012 pursuant to Rule 497 for the retirement class shares of two of the
Registrants series (Accession No. 0001193125-12-411764).

Please contact me at the number referenced below if you
have any questions regarding this filing.